SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e62d3e30687801d4707310392d6637cf4786be7818eaeb0650e5fae939d54e70' 
  AND token = 'WZswMRAXNvHn5PQNGlpf8y/1FOedWL/lD8CfJ4iKt+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}